trace: remove parent_levels session argument

The argument was originally designated to restrict the reach of the
trace monitor but the idea remained unimplemented. It is now superseded
by the use of the trace-session label as trace-subject filter.

Issue #847

repos/base/include/trace_session/connection.h

@@ -35,13 +35,11 @@ struct Genode::Trace::Connection : Genode::Connection<Genode::Trace::Session>,
 	 *
 	 * \param ram_quota        RAM donated for tracing purposes
 	 * \param arg_buffer_size  session argument-buffer size
-	 * \param parent_levels    number of parent levels to trace
 	 */
-	Connection(Env &env, size_t ram_quota, size_t arg_buffer_size, unsigned parent_levels)
+	Connection(Env &env, size_t ram_quota, size_t arg_buffer_size)
 	:
 		Genode::Connection<Session>(env, Label(), Ram_quota { 10*1024 + ram_quota },
-		                            Args("arg_buffer_size=", arg_buffer_size, ", "
+		                            Args("arg_buffer_size=", arg_buffer_size)),
-		                                 "parent_levels=",   parent_levels)),
 		Session_client(env.rm(), cap())
 	{ }
 

repos/base/src/test/migrate/main.cc

@@ -59,8 +59,7 @@ struct Migrate
 	Timer::Connection  timer  { env };
 	Migrate_thread     thread { env };
 	Trace::Connection  trace  { env, 15 * 4096 /* RAM quota */,
-	                                 11 * 4096 /* ARG_BUFFER RAM quota */,
+	                                 11 * 4096 /* ARG_BUFFER RAM quota */ };
-	                                 0         /* parent levels */ };
 
 	Signal_handler<Migrate> timer_handler { env.ep(), *this,
 	                                        &Migrate::check_traces };

repos/gems/sculpt/launcher/trace_logger

@@ -8,7 +8,6 @@
 	<config verbose="yes"
 	        session_ram="90M"
 	        session_arg_buffer="1M"
-	        session_parent_levels="3"
 	        period_sec="10"
 	        default_policy="null"
 	        default_buffer="4K">

repos/gems/src/app/trace_recorder/monitor.h

@@ -114,8 +114,7 @@ class Trace_recorder::Monitor
 		Timer::Connection              _timer            { _env };
 		Trace::Connection              _trace            { _env,
 		                                                   TRACE_SESSION_RAM,
-		                                                   TRACE_SESSION_ARG_BUFFER,
+		                                                   TRACE_SESSION_ARG_BUFFER };
-		                                                   0 };
 
 		Signal_handler<Monitor>        _timeout_handler  { _env.ep(),
 		                                                   *this,

repos/gems/src/lib/vfs/trace/vfs.cc

@@ -383,7 +383,7 @@ struct Vfs_trace::Local_factory : File_system_factory
 	}
 
 	Local_factory(Vfs::Env &env, Xml_node config)
-	: _env(env), _trace(env.env(), _config_session_ram(config), 512*1024, 0)
+	: _env(env), _trace(env.env(), _config_session_ram(config), 512*1024)
 	{
 		_trace.for_each_subject_info([&] (Trace::Subject_id   const id,
 		                                  Trace::Subject_info const &info) {

repos/os/recipes/pkg/test-trace_logger/runtime

@@ -47,7 +47,7 @@
 
 		<start name="trace_logger">
 			<resource name="RAM" quantum="80M"/>
-			<config verbose="yes" priority="no" sc_time="no" session_ram="10M" session_parent_levels="1" session_arg_buffer="64K" period_sec="3" default_policy="null" default_buffer="1K">
+			<config verbose="yes" priority="no" sc_time="no" session_ram="10M" session_arg_buffer="64K" period_sec="3" default_policy="null" default_buffer="1K">
 
 				<policy label_prefix="cpu_burner" thread="ep"/>
 

repos/os/recipes/pkg/trace_logger/runtime

@@ -11,7 +11,6 @@
 	<config verbose="no"
 	        session_ram="90M"
 	        session_arg_buffer="1M"
-	        session_parent_levels="1"
 	        period_sec="10"
 	        default_policy="null"
 	        default_buffer="8K">

repos/os/src/app/top/main.cc

@@ -282,17 +282,12 @@ struct App::Main
 {
 	Env &_env;
 
-	enum {
-		PARENT_LEVELS = 0
-	};
-
 	size_t arg_buffer_ram  { 12 * 4096 }; /* ~ 190 trace Subject_info objects */
 	size_t trace_ram_quota { arg_buffer_ram + 4 * 4096 };
 
 	Reconstructible<Trace::Connection> _trace { _env,
 	                                            trace_ram_quota,
-	                                            arg_buffer_ram,
+	                                            arg_buffer_ram };
-	                                            PARENT_LEVELS };
 
 	static uint64_t _default_period_ms() { return 5000; }
 
@@ -369,7 +364,7 @@ void App::Main::_handle_period()
 	_trace_subject_registry.flush(*_trace, _heap);
 
 	_trace.destruct();
-	_trace.construct(_env, trace_ram_quota, arg_buffer_ram, PARENT_LEVELS);
+	_trace.construct(_env, trace_ram_quota, arg_buffer_ram);
 }
 
 

repos/os/src/app/trace_logger/README

@@ -18,7 +18,6 @@ policy.label:
 !         sc_time="no"
 !         session_ram="10M"
 !         session_arg_buffer="4K"
-!         session_parent_levels="0"
 !         period_sec="5"
 !         default_policy="null"
 !         default_buffer="4K">
@@ -53,9 +52,6 @@ This is a short description of the tags and attributes:
 :config.session_arg_buffer:
   Optional. Size of the trace sessions argument buffer.
 
-:config.session_parent_levels:
-  Optional. Number of parent levels to trace.
-
 :config.period_sec:
   Optional. Length of processing/export interval in seconds.
 

repos/os/src/app/trace_logger/config.xsd

@@ -41,7 +41,6 @@
 			<xs:attribute name="sc_time"               type="Boolean" />
 			<xs:attribute name="session_arg_buffer"    type="Number_of_bytes" />
 			<xs:attribute name="session_ram"           type="Number_of_bytes" />
-			<xs:attribute name="session_parent_levels" type="xs:nonNegativeInteger" />
 			<xs:attribute name="default_policy"        type="Trace_policy_name" />
 			<xs:attribute name="period_sec"            type="Seconds" />
 			<xs:attribute name="default_buffer"        type="Number_of_bytes" />

repos/os/src/app/trace_logger/main.cc

@@ -43,7 +43,6 @@ class Main
 		{
 			size_t       session_ram;
 			size_t       session_arg_buffer;
-			unsigned     session_parent_levels;
 			bool         verbose;
 			bool         prio;
 			bool         sc_time;
@@ -57,8 +56,7 @@ class Main
 
 		Trace::Connection _trace { _env,
 		                           _config.session_ram,
-		                           _config.session_arg_buffer,
+		                           _config.session_arg_buffer };
-		                           _config.session_parent_levels };
 
 		Timer::Connection _timer { _env };
 
@@ -235,7 +233,6 @@ Main::Config Main::Config::from_xml(Xml_node const &config)
 		                                              Number_of_bytes(1024*1024)),
 		.session_arg_buffer  = config.attribute_value("session_arg_buffer",
 		                                              Number_of_bytes(1024*4)),
-		.session_parent_levels = config.attribute_value("session_parent_levels", 0u),
 		.verbose             = config.attribute_value("verbose",  false),
 		.prio                = config.attribute_value("priority", false),
 		.sc_time             = config.attribute_value("sc_time",  false),

repos/os/src/app/trace_subject_reporter/main.cc

@@ -156,7 +156,7 @@ struct App::Main
 {
 	Env &_env;
 
-	Trace::Connection _trace { _env, 128*1024, 32*1024, 0 };
+	Trace::Connection _trace { _env, 128*1024, 32*1024 };
 
 	Reporter _reporter { _env, "trace_subjects", "trace_subjects", 64*1024 };
 

repos/os/src/server/cpu_balancer/trace.h

@@ -57,7 +57,7 @@ class Cpu::Trace
 			_arg_quota += upgrade;
 
 			_trace.destruct();
-			_trace.construct(_env, _ram_quota, _arg_quota, 0 /* parent levels */);
+			_trace.construct(_env, _ram_quota, _arg_quota);
 
 			/*
 			 * Explicitly re-trigger import of subjects. Otherwise

repos/os/src/test/trace/main.cc

@@ -146,7 +146,7 @@ struct Test_out_of_metadata
 
 		try {
 			Trace::Connection trace(env, sizeof(subject_ids) + 4096,
-			                        sizeof(subject_ids), 0);
+			                        sizeof(subject_ids));
 
 			/* we should never arrive here */
 			struct Unexpectedly_got_no_exception{};
@@ -168,7 +168,7 @@ struct Test_out_of_metadata
 			Test_thread thread5 { env, "test-thread5" };
 
 			Trace::Connection trace(env, sizeof(subject_ids) + 5*4096,
-			                        sizeof(subject_ids), 0);
+			                        sizeof(subject_ids));
 			trace.subjects(subject_ids, MAX_SUBJECT_IDS);
 
 			/* we should never arrive here */
@@ -187,7 +187,7 @@ struct Test_tracing
 {
 	Env                     &env;
 	Attached_rom_dataspace   config       { env, "config" };
-	Trace::Connection        trace        { env, 1024*1024, 64*1024, 0 };
+	Trace::Connection        trace        { env, 1024*1024, 64*1024 };
 	Timer::Connection        timer        { env };
 	Test_thread::Name        thread_name  { "test-thread" };
 	Test_thread              thread       { env, thread_name };